Chasse, 42, died Sept. 17 after an encounter with police in the heart of Portland's chichi Pearl District. The schizophrenic man who was known to friends as "Jim Jim" was, according to one officer's testimony, "doing something suspicious or acting just, um, odd."

When Multnomah County Sheriff's Deputy Brad Burton and Portland Police Officer Christopher Humphreys approached Chasse, he ran and the officers ran after him. Portland Police Sgt. Kyle Nice was also nearby and responded.

Police estimate that initial contact took place at 5:18 pm. Chasse was pronounced dead by Providence Hospital staff at 7:04 pm. The events of that one hour and 46 minutes (the length of the movie The Usual Suspects) are already the subject of much debate in the city and will almost certainly be the subject of litigation.

Police Chief Rosie Sizer may be right to denounce those who plastered fliers with the officers' pictures and the incitement "Stop me before I kill again!" on telephone poles in Northeast Portland. That will only widen the rift between Portlanders and their police department.

But she was only half right when she urged in The Oregonian last week, "What would be productive at this point is a focus on the larger picture. Although this death is a tremendous tragedy, the real debate should focus on how our society is fulfilling its caretaker role for people who suffer from mental illness."

No one's saying that debate shouldn't happen. And Portland Mayor Tom Potter took an important step when he announced on Monday he wants to spend $500,000 to train patrol officers in crisis management.

But a review by WW of transcripts, reports and data from the police and medical examiner, along with other interviews, make it clear that this case still demands more scrutiny. And answers.

The incident should be probed further until a full picture emerges of the events that led to James Chasse's death.

"To place any of the burden on [Chasse's] shoulders or the mental-health system is a diversion," says Jason Renaud, a volunteer with the Mental Health Association of Portland. "Police brutality and mental-health reform are separate issues. By tangling them up, you won't solve either one of them."

Let's start with the question of "police brutality."

The official investigation concluded that Chasse died from "broad-based" trauma to his chest, caused solely when Officer Humphreys accidentally fell on top of Chasse. Chasse weighed 145 pounds. Humphreys outweighs him by about 100 pounds.

One month after Chasse died, the Portland Police Bureau said, "Based on all the information available at this time, evidence suggests that the pursuing officer landed on Mr. Chasse as they fell to the ground" and noted that the injuries were "consistent with [a] body landing on Mr. Chasse against [a] hard surface."

The bureau relied on the finding by the state's chief medical examiner, Karen Gunson, that Chasse was killed by "blunt force chest trauma" that was caused "by another person or a fall."

The Multnomah County district attorney's office presented a grand jury with this evidence and testimony from 30 witnesses. On Oct. 17, grand jury members cleared the officers of any criminal wrongdoing. The officers may still be subject to disciplinary action if a department review finds they violated any Bureau policies.

Some, however, balked at the ruling.

Oregonian columnist Steve Duin wrote in an online column on Oct. 21: "The veteran rugby player at The Oregonian was one of the first to ridicule the laughable assertion ... [Chasse] died because a cop fell on top of him, fracturing 16 of his ribs and breaking a total of 26 different bones in the front and back of his rib cage. If that's the way it worked, he said, a dozen rugby players would die every weekend out at Delta Park."

Portland lawyer Tom Steenson, who represents Chasse's family, hired one of the most experienced and storied pathologists in Oregon, Dr. William J. Brady. Already Brady has raised serious questions about the official explanation of events, based on the information in the medical examiner's report.

He expects to complete his own autopsy of Chasse in the coming weeks. Brady is also asking questions about the lack of injury to Chasse's joints and extremities, which are more fragile than the body's core and normally more susceptible to breaks.

According to Steenson, Brady is also questioning whether the location and severity of the fractures is consistent with someone falling on him. Brady believes they may have instead been caused by police violence.

If the medical nuances are difficult for a layperson to sort through, the inconsistencies in the eyewitness accounts are even more confusing.

Humphreys told investigators he didn't fall on Chasse. "I just went boom, down right on the ground," he said. "I fell on the sidewalk. I went right, right over and past him."

Burton couldn't remember exactly what happened. Nice reported, "It appeared that Officer Humphreys kind of landed slightly off the subject. Kind of half on his right side and half on the ground."

Police have said that even though the officers' accounts don't agree, the sum of the available information, which also includes interviews with witnesses (that have not yet been released to the public), points to Humphreys falling on Chasse.

Critics have pointed to the inconsistency in the cops' testimony as evidence the bureau is just trying to protect itself. But wouldn't it be even more suspicious if their stories matched up on every point?

Daniel Reisberg, chairman of the psychology department at Reed College, studies eyewitness testimony. He says there's no hard-and-fast rule about which witnesses to trust when they give differing accounts of the same event.

"Even if the witnesses are being totally honest and sincere, and as accurate as they can be, it's still possible—maybe even easy—for them to remember things differently," says Reisberg, who could offer no comment on the specifics of the Chasse case.

Memory, he says, is not just a video replay of what happened. It includes what one was paying attention to, a mix of what one sees and what one expects to see, and even information that one takes in after an event.

If Humphreys didn't fall on Chasse, how did he sustain his injuries? The only obvious answer is: from a beating.

There is no dispute that once Chasse was on the ground, police punched and kicked him repeatedly in their struggle to restrain him.

As uncomfortable as it is to talk about, officers do not appear to have encountered the kind, gentle Jim Jim whose persona has emerged from the recollection of family and friends since his death.

By all accounts Chasse was scared and fought back mightily—both before and after police tried to use a Taser on him.

"I've never seen anybody look at me like that with the sheer terror in their eyes," Humphreys recalled.

"He was pretty wild-eyed during the whole thing and, uh, just grittin' his teeth and snapping," Burton says. "He was just sort of blindly fighting as hard as he could."

Chasse's ferocity took the officers by surprise.

"He was twisting and turning so that it looked like he was possibly pulling his, uh, shoulders out of socket," Burton told investigators. "At one point he had his, you know, his legs facing the ground and his chest facing us, and then vice-versa and, and kicking and screaming."

According to their testimony to investigators, the officers struck Chasse as he tried to bite them while they were attempting to place him in restraints.

"As he's squirming around and not putting his hands behind his back and biting and kicking, um, I had, I punched him, I believe, once, maybe, maybe more in the, in the back.... At some point either before or after the Tasing I had used the knuckle of my right index finger and just sort of pressure-pointed his ribs for pain compliance," Burton told investigators.

"I don't see Mr. Chasse's head, but I see Sgt. Nice, uh, strike one time, one time with a closed fist," Humphreys told investigators. "Um, I didn't actually see where it landed, but it was up in the shoulder/head area."

And a little later, Humphreys continued, "I just see teeth as he's coming up. And I mean, his teeth are right on my arm. I pull my fist back and uh, uh, basically just use my forearm and I just draw it back and it strikes him across the face and then I come down with a closed fist strike across Mr. Chasse's face."

Nice told investigators, "I looked down, and he had rolled up on his side again and gotten a hold of the cuff of my right pant leg with his teeth again. I pulled my right foot back and kicked him in the upper chest. I told him, 'Don't [bite] me.'"

Nice also described putting a knee into Chasse's shoulder blade in order to pin him down.

Despite those blows, state medical examiner Gunson told WW the injuries that killed Chasse were not consistent with the individual impacts of punches and kicks.

According to her findings, which the grand jury decision supports, the strikes by officers were incidental to his death and not the main cause.

In the coming months, the Bureau will review whether the officers' blows were an appropriate reaction to Chasse's behavior.

But even if they determine the entire incident followed policy, it doesn't controvert the astonishing fact, first reported by WW, that Humphreys is one of the department's top force users.

Last Tuesday, police released data on its officers' use of force to WW under a public-records request. After analyzing the data, WW on Wednesdaybroke the news on its website that only one other officer at the Police Bureau has used more force than Humphreys since the department started to track those figures a couple of years ago (see "Chasse Cop's History," wweek.com, Oct. 25, 2006).

According to the database, which includes more than 8,500 reports from 785 officers, Humphreys is No. 2, with 78 recorded incidents in approximately two and a half years. A further breakdown shows he is also among the top officers for striking suspects and for incidents in which suspects were injured. Of 17 injuries linked to Humphreys, two suspects were taken to a hospital.

Humphreys and 12 other officers make up a vastly disproportionate percentage of force incidents. Out of about 1,000 officers, the 13 are responsible for 10 percent of all use-of-force incidents, WW found. Police say it's unfair not to consider officers' assignments when comparing officers' uses of force.

Humphreys' supervisor says his numbers are higher than other officers' because he frequently arrests suspects in drug stings around the transit lines. After police completed their investigation, Humphreys resumed his duties.

Last Friday, both The Oregonian and the Portland Tribune reported the city had already paid out $90,000 last year to settle an excessive-force claim involving Humphreys. In it, Humphreys was accused of striking a man 30 times with his baton before he discovered the man wasn't the suspect he was after. Under the settlement, Humphreys and the other officers involved admitted no wrongdoing.

According to the Police Bureau's internal-affairs division, Humphreys, a seven-year department veteran, has seven complaints in his file dating back to 1999. He has two from this year, and before that the most recent one dates from 2003. At the same time, Humphreys also has 13 commendations or citizens' letters of appreciation in his file and was the recipient of the department's highest honor, the Medal of Valor, for helping to save four people from an apartment fire.

Even if Chasse's injuries were completely accidental, it doesn't explain why he never received the medical attention that might have saved his life.

According to a police timeline, Sgt. Nice called for a "Code 3 Medical respond for an unconscious male" about five minutes after the initial contact with Chasse. They thought perhaps he had suffered a drug overdose, Burton told investigators.

Medics from American Medical Response, the ambulance company that holds the exclusive county contract for emergency services, arrived in less than three minutes. They were on the scene, along with medically trained Portland firefighters, for the next 16 minutes.

According to a "Fact Sheet" on the incident released by police Oct. 17, AMR medics checked Chasse's vital signs and found them normal—his blood pressure 110/73, a pulse of 100 beats per minute and a respiration rate of 18 to 20 breaths per minute. They also reported Chasse fought them as they tried to render aid.

Chasse family attorney Steenson says Brady believes it unlikely that Chasse's vital signs would have been normal, given the extent of his injuries.

Once medics had examined Chasse, Nice says he "had some conversations with the ambulance staff. I confirmed he was stable. ... They offered, they asked if I wanted him transported [to a hospital]. I said no, we have criminal charges on him."

AMR employees later declined to be interviewed by Portland police detectives about what happened. That's because under federal law they're not allowed to talk about patient information without a subpoena, says Randy Lauer, AMR's regional director of Oregon operations. They did testify, however, before the grand jury.

The protocol for medical response is that if a patient is unconscious, medics have his "implied consent" to take him to the hospital. But if the patient's legal guardian is present, the guardian gets to make the decision. According to the medical examiner's narrative, medics say they left the decision up to the officers.

David Lillegaard, who works near the Chasse scene at Rudy's Barbershop, didn't see the initial fight, but witnessed what happened right afterward from 20 to 30 feet away. He says Chasse appeared to be unconscious for at least part of the time emergency responders evaluated him.

"At one point I thought he was dead," says Lillegaard. "To me, from that situation, there didn't seem to be a reason not to take him to the hospital—just from the blood on the ground and the fact he was passed out."

Lillegaard also says officers nudged Chasse with their feet from time to time as if to check whether he was conscious.

Humphreys rode with Chasse to the Multnomah County Detention Center downtown and told investigators that Chasse did not complain of injuries. He said Chasse did talk, but "a lot of it was that same like a mumble, mumble, mumble...like a gibberish," Humphreys told investigators. "I get about halfway through his Miranda rights and, uh, he goes, 'What did I do, what did I do?'"

So, either Chasse had massive internal injuries that no one detected at the scene or they occurred later—sometime in the four minutes between the ambulance leaving and the officers leaving to transport Chasse to jail, hogtied in the back of the police car, or in the eight additional minutes it took them to arrive at the jail. (Though no one, so far, is suggesting that happened.)

Once he arrived at the jail, the county medical staff took one look at Chasse though a window in his cell and decided he wasn't in good enough shape for them to admit him. A jail nurse described him as "twitchy," which Steenson believes may be evidence he was having seizures.

County policy says the jail does not accept inmates who are in need of more than minor medical attention.

Humphreys and Burton once again loaded Chasse in the back of a patrol car. On the way to the hospital, it became clear something was seriously wrong with Chasse. Humphreys looked back at their prisoner and saw his arm was stark white.

They pulled over and tried to resuscitate Chasse. Medics arrived within five minutes but could not save him.

While many questions remain, one thing is certain: The death of James Chasse at the hands of Portland police has galvanized the community as few events in the city's recent history have—and many are using it as a touchstone to call for additional police training and mental-health services.

Among several hundred people who turned out for a public memorial last Friday at the First Congregational United Church of Christ was Bill Faricy of Southeast Portland, one of many in the crowd who had never met Chasse.

"It seems like the pattern we're supposed to accept is, about one civilian a year gets killed," he says. "I don't want to see this die down. I don't want to see it be another 'incident.'"

WW intern Alice Joy contributed to this story.

For blunt "impact" strikes (which include hand, foot, baton and flashlight strikes), Humphreys is tied for No. 1 among the 295 officers who reported using such strikes. He reported using strikes 25 times. All but one of those was with his hands or feet. The remaining instance was marked "other."

For physical force used to restrain suspects (such as "take downs," "pressure points" and "control holds," but not including just placing a suspect in handcuffs), Humphreys is tied for No. 2 among the 422 officers who reported using that type of force.

Among officers whose uses of force caused injury to suspects, Humphreys is No. 5 out of 413 officers who reported injuring suspects. Suspects were injured in 17 of his 78 incidents—that's more than one injury for every five uses of force and higher than the overall average.

The Portland Police Bureau's top 33 officers who reported using force since the department started tracking those statistics are responsible for 20 percent of all uses of force. They make up just more than 4 percent of officers who reported using force and an even smaller percentage of the overall department.

Dr. William Brady was fired from his job as the state medical examiner in the mid-'80s for selling tissue samples from bodies to pay for office amenities. He sued, and a jury sided with him, awarding him $300,000.

An extensive archive of local media stories about the Chasse case, as well as primary source documents and photos, can be found at mentalhealthportland.org.